A Mate's Infidility
by Sweetchinmusicaddict
Summary: Sesshomaru cheats on Sango while they are mated. He realizes it's the biggest mistake he has ever made and he is desperately trying to get her to love him again. He will endure anything to get his mate back.
1. Discovery

**I DO NOT OWN INUYASHA OR THE CHARACTERS IN INUYASHA. THAT IS ALL.**

Sesshomaru cheats on Sango while they are mated. Sesshomaru Mates another woman while in the throes of passion. He realizes it's the biggest mistake he has ever made and he is desperately trying to get her back.

As Sesshomaru patrols his lands contemplating about how his life has gotten so complicated. He wonders about his estranged wife, the infamous demon slayer, Sango. '_It's my fault and now I am left with a shell of what use to be my mate. I never had the misfortune to regret a decision before I allowed myself to be entranced by a human.' _It has been only 6 months since that fatal day, the day Sesshomaru lost the only woman he could ever.

6 Months ago

"Good day Hiroku, has his Lordship returned?" asked Sango. It was strange, she thought that Sesshomaru had returned, but he did not come and see her like usual. Usually whenever the Great Demon Lord returns, she is always the first person he greets.

"Yes, my Lady the Great Lord has returned, but he asked not to be disturbed by anyone" answered Hiroku. Hiroku saw the Great Demon Lord enter his bedchambers and also observed a young demoness enter the room as well, but he did not want to relay that message to Sango. He quite liked Sango being the Lady of the West and did not want her to be hurt because of Sesshomaru's infidelity.

"Well that will be all Hiroku, you may leave." Sango stated eagerly. Hiroku shook his head as he watched her eagerly walk down the hall and turn the corner. Sango wanted to see Sesshomaru as quickly as possible. She missed her demon greatly and wanted nothing more than to curl up next to him while he her gently strokes her hair. She loves that her mate gives her the special honor of seeing him in his gentle state. Sango continues to walk down the many corridors of her mate's castle observing the splendor and grandeur of it all, until she reached their private quarters. When Sango goes to open the door open she hears strange noises emanating from their bedroom. _'That's odd, what are you doing, oh mighty dog demon?_' she thinks to herself. As she peeks through the door she sees the heart breaking sight she thought she never would see.

There in their bed, is Sesshomaru lying on top of a young demoness in the throes of passion. _'Wha…this…this can't be happening...'_ she thinks. Sango feels like her whole world is crashing, her heart it shattering into minuet pieces, like her soul is being viciously ripped from her body. She wants to tear away from the heartbreaking scene; but she is frozen to the ground, while she watches her mate commit a heinous act. While she is in the doorway, the door creaks drawing the attention of her "mate". For three unbearable seconds their eyes meet, dark brown clashing with molten gold.

Sesshomaru's POV

While I was in the middle of giving this young demoness the best time of her existence, I heard the grown of the door. Immediately I became angry, _'I gave orders for no one to disturb me for any reason. Whoever this is will come to a slow and pain filled death at the hands of this Sesshomaru!'_ I thought. But when my eyes clashed with those once warm brown eyes of my mate, I knew I committed the first act I would ever regret. Instead of the warm loved filled eyes I grew so accustomed to, I saw in them heartbreak, sorrow, betrayal, and anger. And then there was nothing, her eyes once filled with so many emotions one couldn't possibly know them all now were lifeless and cold, devoid of all emotion. That was the first time I ever felt fear. As I watched her turn her back to me, I tried to reach her through our mate mark and there is when I felt fear for the second time of my life, I felt nothing. I couldn't feel her emotions or her thoughts. If I didn't see her retreating form, smell or hear her, I would never know that see was there at all. As I scrambled to put on my clothes and chase the only female I would ever allow myself to love, I turn to the demoness in my bed "Get out! You will no longer be needed!" I said. The demoness had the audacity to reply "You don't need that filthy human, when you have something as lovely as me in your bed chambers," she said. If I was not trying to get to the love of my existence before it was too late I would have killed her on the spot. Glare so cold ice would be envious I said, "Leave these lands before I disembowel you slowly and have your family watch." After that she believed this Sesshomaru would do such that, and quickly got dressed and left. As I finished getting dressed, I caught up with my hastily retreating mate.

Sango's POV

As our eyes clashed, I felt all of my emotions well up unbearably, until I just left it all go. I felt hollow devoid of everything. I had not feelings, no heart, and no soul, just hollow. The only thought that came to mind was to walk away for the scene. And that is exactly what I did. I could vaguely hear the shuffling of clothes and assumed that he was going to come and try to stop her from leaving. I figured no matter what he did or say it wouldn't stop me from going, so there was no need to rush. Before I could round the second turn, I felt him grab my arm. I violently yanked my arm away from him as if he burned me, I saw the hurt flash briefly in his eyes before his masked dropped into place once more, but I did not care. As I meet his eyes I saw the emotions he has long sense lost the ability to hide from me, I saw regret and guilt and said in a voice devoid of everything "Don't touch me." As we stood in the hallway for what seemed like an eternity I waited for him to say something. _'Well, I guess for the first time in our five years of marriage, he is speechless. If he does not break the silence then I will.'_ Before I could speak I heard him begin what I am sure will be an elegantly worded explanation that he thinks will make me fall prey to his charms._ 'I will not fall prey to your charms, eyes, or elegant words of apology. I always forgave you no matter what happened, but I am sorry that I will not forgive this transgression.'_

Sesshomaru's POV

When I caught up to my mate, I grabbed her arm. She violently removed her arm from my grasp and momentarily hurt flicked in my eyes before I dawned my emotionless mask once again. As I listened to her tell me not to touch her in the most emotionless voice I ever heard from her. "Sango, I-" "Why?" before he could finish he was cut off by Sango. As he continued to look into her lifeless dark brown eyes, he answered honestly "I wanted to feel how it felt to be with a demoness again." As I waited patiently for her to respond to my statement, a fear unknown to me welled up inside of me. I never thought that I would lose her but the possibility was far too likely in this situation. When I saw her prepare to speak, I unknowingly held my breath, she said…


	2. Revenge Best Served Cold

**I DO NOT OWN INUYASHA OR THE CHARACTERS OR INUYASHA. THAT IS ALL.**

**AN:** Thanks samy-sama for being my first review and I plan to make him suffer =). One cannot cheat on Sango and expect no revenge!

Last time on A Mate's Infidelity…

_When I caught up to my mate, I grabbed her arm. She violently removed her arm from my grasp and momentarily hurt flicked in my eyes before I dawned my emotionless mask once again. As I listened to her tell me not to touch her in the most emotionless voice I ever heard from her. "Sango, I-" "Why?" before he could finish he was cut off by Sango. As he continued to look into her lifeless dark brown eyes, he answered honestly "I wanted to feel how it felt to be with a demoness again." As I waited patiently for her to respond to my statement, a fear unknown to me welled up inside of me. I never thought that I would lose her but the possibility was far too likely in this situation. When I saw her prepare to speak, I unknowingly held my breath, she said…_

Sango's POV

'_Sesshomaru, I want you to suffer each and every day until or if I say you have suffered enough. I think I know what your punishment shall be.'_ As I begin to speak, I notice that this is the first time Sesshomaru has ever been nervous. The demon so sure of himself and confident about all of the things he does, is nervous about what a human will say. I think _'My My Sesshomaru, look how the mighty have fallen.' _I begin to speak the words that will mark the beginning of his tormenting, "Sesshomaru, though you have decided to through away your honor on a whim, I still have mine. I will stay with you and keep up the appearance of the bliss filled life I thought we both shared. But in private I do not want you to look at me, touch me, speak with me, or even entertain the thought of having sex with me. You will be forced to watch the shell of the mate you once loved each and every day of your life. I may find joy and happiness again, but realize it will not be with you. You will be forced to watch me enter act civilly with everyone else except you. And that, my dear demon lord, is your punishment." I see the rage build behind those golden eyes of his and I wait for the controlled explosion.

Sesshomaru's POV

'_I cannot believe the audacity she has to think she can do these things to this Sesshomaru! She maybe my mate but I am still the Lord of the Western Lands! No one does a thing without my approval and that includes my mate!'_ As I feel the intensity of my rage build up over what my mate has deemed my "punishment", I try to control it. In a voice so cold and vicious it would make lesser demons parish I said' "Who do you think you are? Do you really think you can stop this Sesshomaru if he wants to do anything to you? No one can control me! Not you or anyone else! Do you think that just because you are my mate you will escape my wrath?" The instant I said those words and looked at the implications, is where I had regret for the second time of my life. I watched as her face became even more death like, which I thought was impossible. After what felt like an eternity, she spoke, "Well, it would seem that I am truly no one to this Sesshomaru. I once believed that you would never take another to our bed or harm me but I was wrong on both accounts it seems. Be warned Lord of the West that I will defend myself against…any…person that wishes to do things that I wish not to do. I do realize Lord of the West that you are indeed much more powerful than me, but do not forget that I am a master demon hunter and will forever be one."

Sango's POV

My threat hung openly in the air as I judged his reaction to my words. I watch so many emotions cross his face that were never there at one point. He allows me to see the hurt and guilt he feels for even implying that he would harm me. He begins to speak, "This Sesshomaru has never meant to hurt you. I would never bring harm to you. I have never allowed anyone to capture my heart and soul as you have undoubtedly captured them both soundly." He embraces me and I fight back the urge to tell him this qualifies as touching me, but I let him get a goodbye hug, even if he is not aware that it is such. He whispers in my ear, "My love, I am sorry; forever more you are the only entity that will ever have this Sesshomaru completely, mind, body, and soul. I regret my actions that caused you to lock away the woman I feel so madly and completely in love with. I will do everything in my power to restore your love for me. I will not rest until you willingly let me back into your heart." As he leans in to kiss me, I turn my head to the side to avoid it. I say in a voice devoid of emotion, "The nerve you have to try to kiss me while that whore's scent still lingers on you. Your words fall on deaf ears my Lord. I will have servants move my things into the bed chamber next to yours. I no longer wish to be in your company. I hope your curiosity has be sated, my Lord. " As I turn around to continue my journey far away from him, I catch a glimpse of the disbelief in his eyes before I turn the corner. After the confrontation I feel all of my emotions come violently back to me. I feel the tears well up into my eyes before I can fully make it down the stairs and out of the castle.

Sesshomaru's POV

'_I cannot believe this is happening. I will not believe that I may have lost my mate.'_ As I watch the retreating form or my mate yet again, I cannot help but to think that I may have just lost the only person, besides Rin, I allow into my heart. That is when the smell hit me, the smell of salt and despair. _'I once promised you, my love, that I would never make you shed tears again. It looks like even this Sesshomaru does not keep every promise and for that I am truly sorry.' _ I walk into my bed chambers and smell the reason for my mate's despair and I suddenly loath myself and the vile demoness I so foolishly allowed in my bed. I call for servants to enter my bed chambers and clean away the scent of my betrayal. I call my personal body guard Bankaru to my side. Bankaru looks at me with that knowing look he has always had ever since we were pups. Once I ordered the servants to leave, Bankaru and I were left alone. Bankaru began to speak, "Sessh what have you done?" I let my mask drop slightly in the presence of Bankaru as I state, "What I have done is my personal business and I do not need your advice at the present moment. Bankaru you are among the very few I call friends and when I need counsel you will be the first to know. As of right now, I desire to be left alone." 'How could I possibly allow my judgment to yield these results? Never in my life have I done something that did not benefit me or would benefit me. This simply cannot due! I must have her back; I will not be without my mate!'

Next Chapter: And with that thought in mind Sesshomaru begins planning how to get his beloved mate back; while Sango plans to extract her revenge.


	3. The Plans

**I DO NOT OWN INUYASHA OR ANY OF INUYASHA'S CHARACTERS. THAT IS ALL.**

**Sorry for the wait guys, trying to get ready for College and all that. But here you go! Enjoy!**

Sango's POV

Once I left the castle, I had to get away to breath, sort through my emotions and fine tune my revenge plot. I went to my favorite place, the gardens. The gardens are really beautiful; there are flowers of all colors and shades lining the walkway. At the end of the path is a cherry blossom tree, in full bloom, next to a crystalline pond. Going here always relaxes me and it is one of the few places in this castle I can call my own. As I sit down next to the cherry blossom tree I begin to think about my first plan of action, _'First things first, move my things out of Sesshomaru's room.' _I call to a servant because they are never too far away, "Roku, I need you as well as some other servants to obtain my belongings from the Lords room and place them in the bed chambers next to his." Roku looks stunned at what I just asked of him but never the less he answers in the affirmative, "Yes, my Lady." As I watch him set off to the task he has just been told to do, I start to construct the rest of my revenge plot. _'There is a ball coming up in two weeks, it will be the perfect opportunity for me to show him what the rest of his life will truly be like. I will be the most stunning and charming female there. I will make him regret having ever thought of another female that way, being human or demon. Maybe I will even invite the old gang; it's been entirely too long since I have seen them. I wonder how Miroku is doing.' _Sango thought with a very mischievous smile gracing her lips.

Sesshomaru's POV

"I will leave you to your own devices Sessh; just know that you have a really fantastic mate. Fight for her with everything you have. I have never seen you this happy and, as a friend, I do not want you to revert back into your unhappy life again," said Bankaru. As I look at Bankaru I see that his concern for me is out of friendship and I am truly grateful to have such a friend and I tell him as much. "Thank you Bank, I see that your concern for me is admirable and I thank you my friend. Now if you will please leave me, all of you," I say to the servants as well as Bank. As they leave I start to think to myself. _'How could I be so foolish as to allow another in my...our bed! How will I ever prove to her that my love for her is bottomless? I will work my way into your heat again my dear. I am indeed heading into the most important battle of my existence and I will stop at nothing to win.' _After that thought I start to think of ways that I could start to inch my way back into her good graces but for I will let her cool off and think things through. I sit ideal on my bed thinking of things to do to win back my mate, when I hear someone knock on my camber doors. "I do not wish to be bothered." I say fully expecting to hear retreating steps; instead I hear the meek voice of my servant saying "Bu-but the Lady has sent us to collect her things immediately. The Lady requested for us to have her things in her room by sunset and that time draws near." I sigh to myself, how can I deny any request she has of me after the most heinous act I did not three hours ago. "Enter and set about your task quickly." As they enter I figure I cannot just sit ideally by and watch as they take her things. I set about the task of writing her a letter.

Letter Starts

_My dearest Sango,_

_I am truly and utterly sorry for what has been done. I love you more than mere words can express. I love you with my heart, my mind, and my very soul. If it takes my life to convince you that I do truly love you with my whole being, I will be more than willing to pay. Your wish is my command and I will walk to the ends of earth and beyond to prove my love for you. Do not let this wicked act of mine stop the love we share and will share beyond this point. I am confident that I will get you to love me once more, it is impossible for one to love with all that they are, and not have love returned. It is simply impossible. I cannot find the words that can fully describe the regret I have for causing you this pain, because they do not exist. I felt fear for the first time in my life when you looked at me with those emotionless eyes. I feared I would never see the wonderful emotions you have deep within them. I felt fear because I thought I would never again see the happiness you radiate; that I would never again be the cause of your cheer. I love you more than life itself and I would sacrifice the world for you if it would make you smile. I will do everything in my power to make you happy once more. You are the other half of my soul and if I am never honored to see your divine smile again, I think I would go mad. I do not wish for you to drive me to insanity, but if my sanity is the recompense you wish for than by all means take it and smile once more. For your happiness is the only thing in the world I care for my goddess divine._

_Love your mate,_

_Sesshomaru_

As I finish my letter, I seal it with my personal crest. I notice that the servants are almost completed their task. "Roku, come here" I call out; "Once your task is finished place this letter on your Lady's bed." Roku answers, "Yes, my Lord." I watch them finish their task and notice how empty my…our bed chambers feel. There is a void where her presence should be. _'This Sesshomaru has made a grave error in judgment; one that I fear will cost me everything I love. No, I must not think like that. My wonderful Sango is still giving me a chance. I just pray to the gods that I can endure it.'_

Next Time on AMI

Sango ignores him for the coming week and Sesshomaru tries to deal with the void he feels.

Please Review, I like to know what you think :)


	4. Dishonored

AN: Sorry for the long wait. It is my first year of college and fanfiction was put on the back burner, well at least writing it was. But whatever here you go, hope you enjoy it!

A week later

Sango's POV

I am in my new chamber, as far away from Sesshomaru as I can get without raising too much suspicion. Doesn't matter though, the whole castle now knows what happened on that dreadful day a week ago. As I lay down in my room I contemplate how my life has come to this point. Here I am a demon slayer, married to, for all intents and purposes, the king of demons. The most shocking aspect of my life is that I was, as I thought, happily married to the king of demons. If you would have told me ten years ago that I would be here I would have laughed in your face and tried to hit you. But no, here I am. In this huge castle, with hundreds of demons surrounding me, married to a cheating demon lord, dishonored by an act I did not commit and lonelier than I have been in a while. I burry my face in my pillows and I scream like there is no tomorrow. Gone is the sense of security I had in my marriage, gone is the trust I had in Sesshomaru. I am just filled with frustration, sadness, bitterness, and the ever resentment. No I do not resent marrying the arrogant and at times heartless demon, not by a long shot. I resent the fact that I am disgraced, that I feel so horrible, and that the only person I want to comfort me is the cause of my pain. But I cannot sit here and wallow in my pain. I must get ready for the day for tonight, my revenge will start.

Sesshomaru's POV

I sit at my desk thinking about the woman who has managed to avoid me the entire week, Sango. It is no surprise that she has managed a task so many powerful demons have failed at; after all she is the best of the best. Only the best are acceptable for this Sesshomaru. The incident was a horrendous lapse in judgment, one that I fear will cost me the most exquisite thing I ever had. My life has taken a dreadful turn and I am the architect of not only my own suffering, but even worse, my Sango's as well. The pain and humiliation caused by my most dreadful actions will forever haunt my Sango. Not only have our marriage been disgraced but the Lady herself and none of it was of her doing. Sango had enough derision to deal with for being the mate of a demon, let alone a demon as powerful as me, and having the history of being a demon slayer. My actions have undoubtedly increased the amount of mockery her name has to endure. Though no one is foolish enough to do it while in my presence, the scorn still happens. My dearest Sango, what have I don't to you? The trust you had in my as both your mate and protector is surely greatly diminished if not gone. If you were to believe me when I say that my transgressions will never be repeated for the rest of our lives, the happiness I would exude will be immeasurable. But alas, it is foolish of me to hope for your forgiveness so soon. How can you believe a person you have lost your trust in? Who broke the vows he swore to uphold till the very end of his nearly immortal life. You would not be able to believe him and it would be foolish of you. My tie of contemplation has reached its end for today. I must prepare for the rest of the day and the ball.

Sango's POV

After getting dressed for today I decided to go get lunch seeing as it is nearly noon. As I walk from my chambers to the kitchen, I try to ignore the barely cloaked sneers at my humanness and the hidden smiles at my disgrace. It is a long walk endured since I became the Lord of the West's mate, just with the new element of disgrace. Head held high I walk on ward, I am still the last demon slayer and no matter what I have done to disgrace my people, the title will forever be mines to bear no matter what. That alone deserves respect but I know it is a title that awards me only scorn and contempt. The only reason I have not been attacked yet is because of my connection with the demon lord and now that connection appears to be severed it is a very dangerous situation for me to be in. But like any good slayer in the presence of demons, I am armed with my hidden daggers and my battle skills. This fact also stays the demons, they know that the Lord of the West requires only the best and he views me as the best. To them that makes me dangerous and it is a fact they keep well in mind regardless of them being demons. I make it to the kitchen with little incident where I am greeted with the sight of the chef cooking massive amounts of food. "Good morning Fumio," I greet with a small smile. He only nods, which I know is not meant to be disrespectful, he just keeps to himself. That trait of his makes him the perfect listening partner. As I start to eat my lunch I start to rant to my ever listening companion, "Today seems to be one of those days, Fumio, where you want to lie in bed and forget for just a moment. Forget that you are one of the only two humans in the castle. Forget about the gossip and rumors. Forget that you cannot go back in time and prevent things from happening or to warn yourself." He does not respond, just continues to cook food like I expect him to. What is not expected is the voice that responds to me. "I truly hope you are not referring to agreeing to be my mate."


End file.
